Also, one member of the athletic department staff, whose name was taken out of the letter "failed at all times to maintain an environment of NCAA rules compliance."

The violations don't include anything related to academic dishonesty or fraud, the school said.

If the allegations are validated by the NCAA's Infractions Committee, the school could face recruiting sanctions, including loss of scholarships or recruiting privileges.

After a lengthy investigation, the NCAA threw out allegations that troubled former player Ricky Clemons received improper academic help to get into Missouri because the charge couldn't be substantiated.

Associate head coach Tony Harvey, top assistant to Quin Snyder, is alleged to have given Clemons $250, an anonymous source familiar with the investigation told The Associated Press on Monday.

Harvey has denied the allegation.

"My story isn't changing," he said Monday.

Other alleged violations between 1999-03 included a breach of ethical conduct by a member of the athletic department staff in trying to conceal rule-breaking; providing meals and transportation for current athletes and recruits; out-of-season league play by team members; impermissible contacts with recruits; and impermissible meals for Amateur Athletic Union coaches.

The notice arrived at Missouri last Friday.

University Chancellor Richard Wallace said Missouri will challenge some of the allegations by a July 1 deadline. A hearing has already been scheduled by the NCAA's Infractions Committee during its meetings Aug. 13-15 in Seattle.

Harvey and Snyder have said no Missouri coaches gave money to Clemons. In a television interview with HBO taped Feb. 21, Clemons replied "yes" when asked whether he had been paid by coaches at Missouri.

Clemons, who has moved to North Carolina, said he didn't know the total amount he received.

Snyder apologized Tuesday for any mistakes he made.

"Mistakes have been made," Snyder told a news conference in the university's alumni center. "I take full responsibility for the commission of those mistakes."